There are numerous ways to encrypt a file or a directory under Linux.
Some of these methods involve deploying specific encryption utilities or public/private key systems such as gpg.
I wanted to deploy a simple method that relies on mainstream tools which are usually present on most if not all Linux systems.
The method described below uses tar and zip/unzip.
Create a Tar Archive
First, tar the folder into a .tar archive:
tar -cvf folder.tar /folder
Create a Password Protected Compressed File using zip
then zip the .tar file:
zip -re folder.tar.zip folder.tar
it will prompt you to enter a password of your choosing and then verify it
to unzip you have to use
This will prompt you to enter the password
tar -xvf folder.tar
this then recreates the directory structure and the contents